North Korean attack on South Korea: 8 provocations of the past decade

North Korea shelled South Korea's Yeonpyeong island Tuesday, killing two South Korean marines and injuring more than a dozen people. South Korea returned fire. Both sides claimed that the other fired first.

While the South has engaged in past attacks – notably in November 2009, when it fired on a North Korean patrol boat, and in June 1999, when it sunk a North Korean vessel – history shows that Pyongyang is often the instigator. A 2007 report from the US Congressional Research Service documents dozens of provocations, ranging from low-level naval warfare to assassinations of South Korean cabinet officers.

Here are seven examples of the North's military provocations over the past decade.

November 2001

On Nov. 27, 2001, North Korean soldiers opened fire across the demilitarized border zone at a South Korean guardpost. South Korean soldiers responded with fire, though none were killed from either side. Another exchange of fire would not be recorded until July 23, 2003.

Despite the Nov. 27 incident, two days later the United States reaffirmed it would provide humanitarian assistance to North Korea and desired to resume talks.